Up to now, the avionics bay is arranged in the bay located under the floor structure of the cockpit and in part in the cargo bay located under the passenger cabin. The expression “avionics bay” means in the present disclosure the whole electric and electronic cabinets above mentioned.
Now, because of the increase of the electric equipment, the cooling of the avionics bay is made, as schematically illustrated on FIG. 1, by a set of two independent circuits comprising: a blowing circuit C1 consisting in an air blowing inlet pipe K1 (arrow Fa) in each cabinet B by coupling with individual channels I1 (arrows Fb), the air then circulating in each cabinet (arrow Fc), and an extraction air C2 for the air having crossed the cabinet B, consisting in individual air extraction channels I2 (arrows Fd) coupled with an outlet extraction pipe K2 (arrow Fe). There are a blowing circuit C1 and an extraction circuit C2 for each of the sides of the airplane. Such circuits are duplicated for safety reasons.
Such circuits pose problems in terms of installation due to the complexity of their shape because of the small volume available. Moreover, in the cargo bay, the integration of the electric/electronic material is also problematic because this area is not secured. The separation to be observed between the redundant systems (cabinets, electric ways, air circuits, etc.) is restricting.
Thus, it has been proposed to integrate the whole avionics bay function into the secured area in front of the aircraft, comprising the cockpit, the front cargo bay and the floor structure between them.
However, the problem of the congestion is then posed abruptly, since such secured front area, in particular the cockpit, is already well filled with the whole equipment and apparatus thereof. The usual blowing and extraction means, consisting in tubes with a strong diameter being interconnected, are now made in a composite material of a weak thickness which can be “worked” for a better integration. Nevertheless, these means present installation constraints being difficult to manage due to the complexity and the volume thereof, as well as through their fragile construction in a light and thin material (in general a composite material).